Light emitting device and method of manufacturing the same

ABSTRACT

An ink jet method known as a method for selectively forming a layer made of a polymeric organic compound is advantageous in that a layer containing an organic compound can be separately colored for emitting light of three colors (R, G, B) at a time. However, this ink jet method is disadvantageous in its poor film formation accuracy, and therefore, it is difficult to control the formation of the film for obtaining the uniformity. As a result, the obtained film is likely to have unevenness. In the present invention, an layer containing an organic compound is formed on the entire surface of a lower electrode connected to a thin film transistor by application. After forming an upper electrode on the lower electrode, an layer containing an organic compound is etched in a self-aligned manner by plasma etching using the upper electrode as a mask so as to allow the selective formation of an layer containing an organic compound. Furthermore, for connection with the upper electrode, the electrical connection is achieved by using an adhesive containing a conductive particle or a paste. Furthermore, a material emitting white light or a material emitting monochromatic light is used as the layer containing an organic compound. The full-color display is achieved by combining the layer containing an organic compound with a color conversion layer or a colored layer.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a light emitting device with alight emitting element that emits fluorescent light or phosphorescentlight upon application of electric field to a pair of electrodes of theelement which sandwich a layer containing an organic compound, and to amethod of manufacturing the light emitting device. In thisspecification, the term light emitting device includes an image displaydevice, a light emitting device and a light source (includingilluminating device). Also, the following modules are included in thedefinition of the light emitting device: a module obtained by attachingto a light emitting element a connector such as an FPC (flexible printedcircuit; terminal portion), a TAB (tape automated bonding) tape, or aTCP (tape carrier package); a module in which a printed wiring board isprovided at an end of the TAB tape or the TCP; and a module in which anIC (integrated circuit) is directly mounted to a light emitting elementby the COG (chip on glass) system.

[0003] 2. Description of the Related Art

[0004] Light emitting elements, which employ organic compounds as lightemitting member and are characterized by their thinness and lightweight, fast response, and direct current low voltage driving, areexpected to develop into next-generation flat panel displays. Amongdisplay devices, ones having light emitting elements arranged to form amatrix shape are considered to be particularly superior to theconventional liquid crystal display devices for their wide viewing angleand excellent visibility.

[0005] It is said that light emitting elements emit light through thefollowing mechanism: a voltage is applied between a pair of electrodesthat sandwich an layer containing an organic compound, electronsinjected from the cathode and holes injected from the anode arere-combined at the luminescent center of the layer containing an organiccompound to form molecular excitons, and the molecular excitons returnto the base state while releasing energy to cause the light emittingelement to emit light. Known as excitation states are singlet excitationand triplet excitation, and it is considered that luminescence can beconducted through either one of those excitation states.

[0006] Such light emitting devices having light emitting elementsarranged to form a matrix can employ passive matrix driving (simplematrix light emitting devices), active matrix driving (active matrixlight emitting devices), or other driving methods. However, if the pixeldensity is increased, active matrix light emitting devices in which eachpixel (or each dot) has a switch are considered as advantageous becausethey can be driven with low voltage.

[0007] Organic compounds for forming an layer containing an organiccompound (strictly speaking, light emitting layer), which is the centerof a light emitting element, are classified into low molecular weightmaterials and polymeric (polymer) materials. Both types of materials arebeing studied but polymeric materials are the ones that are attractingattention because they are easier to handle and have higher heatresistance than low molecular weight materials.

[0008] Known methods for forming these organic compounds into films are,for example, an evaporation method, a spin coating method, and an inkjet method. The spin coating and the ink jet are particularly well knownas methods that allow a light emitting device to display a full-colorimage using a polymeric material.

[0009] However, when the spin coating is used, the organic compounds areformed over an entire film forming surface and therefore, it isdifficult to selectively form the film in which the organic compound isformed only at a portion intended to form the film and the film is notformed at the portion which is not necessary to form the film.

[0010] Further, the active matrix light emitting device is formed with awiring for inputting an electric signal from an external power source toa driver circuit formed above a substrate, and a wiring for electricallyconnecting a light emitting element comprising a cathode, an anode andan layer containing an organic compound formed by an organic compoundformed at a pixel portion with the external power source and therefore,when the organic compound is formed at the portions (terminal portions)of the wirings connected to the external power source, there poses aproblem that ohmic contact cannot be achieved with external powersource. Especially, when the layer containing an organic compound isformed by the spin coating method, it is difficult to lead outelectrodes (cathode or anode) formed on the layer containing an organiccompound to the terminal portions.

[0011] Therefore, the present invention provides a method forselectively forming a polymeric layer containing an organic compound anda connection structure for electrically connecting an electrode (acathode or an anode) provided on the layer containing an organiccompound to a wiring extending from a terminal portion.

[0012] An ink jet method, known as a method for selectively forming apolymeric organic compound film, is advantageous in that differentorganic compounds respectively emitting light of three colors (R, G, B)can be separately applied at a time. However, this method isdisadvantageous in its poor film formation accuracy, and therefore it isdifficult to control the formation of films so as to obtain theuniformity of the film. Thus, the obtained film is likely to haveunevenness. The reasons for such unevenness in the ink jet method are,for example, unevenness in nozzle pitch, unevenness due to the inkjetted in a curved manner, low stage matching accuracy, a timing lagbetween the ink discharge and the stage movement, and the like. Forexample, this ink jet method has problems in implementation conditionssuch as a clogged nozzle for ink jet due to internal viscosityresistance of an ink produced by dissolving an organic compound in asolvent, an ink jetted out from a nozzle which fails to reach a desiredposition, as well as problems for practical use such as increased costdue to the necessity of a dedicated apparatus having a high precisionstage or an automatic alignment mechanism, an ink head and the like.Moreover, since the ink is spread after reaching, a margin is requiredto a certain degree as a space between adjacent pixels. As a result, itbecomes difficult to provide higher definition.

[0013] Therefore, in an active-matrix light emitting device using apolymeric organic compound, the present invention has an object ofproviding a method for selectively forming a polymeric material layer,which is simpler than in the case where the ink jet method is used; thepresent invention has another object of easily forming a structure inwhich an layer containing an organic compound is not formed at ajunction of a wiring to be connected to an external power source.

[0014] A light emitting device conventionally has a problem in thatexternal light (light exterior to the light emitting device) incident onnon-light emitting pixels is reflected by a bottom face of a cathode (aface on the side being in contact with a light emitting layer),resulting in the bottom face of the cathode acting as a mirror. As aresult, the exterior landscape is disadvantageously reflected on aviewing face (a surface facing a viewer side). In order to avoid thisproblem, it is devised that a circular polarization film is attached ona viewing face of the light emitting device so that the exteriorlandscape is not reflected on the viewing face. However, since thecircular polarization film is extremely expensive, the manufacturingcost is disadvantageously increased.

SUMMARY OF THE INVENTION

[0015] In the present invention, a film made of a polymeric material isformed on the entire surface of a lower electrode (first electrode) byapplication, an upper electrode (second electrode) is formed by vapordeposition using a vapor deposition mask. Then, the film made of apolymeric material is etched in a self-aligned manner by plasma etchingusing the upper electrode as a mask, so that the selective formation ofthe polymeric material layer is allowed.

[0016] Furthermore, an auxiliary electrode (third electrode) is formedso that the upper electrode is connected to a wiring extending to aterminal electrode. Moreover, a thickness of the upper electrode mayreduced as long as the upper electrode is resistant against a plasmaetching process. In this case, the resistance may be reduced by theauxiliary electrode formed thereon. As the auxiliary electrode, a metalwiring made of a metal may be used, or an adhesive containing aconductive paste (a nanopaste, a hybrid paste, a nanometal ink and thelike) or a conductive fine particle may be used.

[0017] A structure of the present invention disclosed in the presentspecification relates to, as shown in an example of FIGS. 1A and 1B, orFIGS. 22A and 22B, a light emitting device including:

[0018] a pixel portion including a plurality of light emitting elements,a driving circuit and a terminal portion, between a first substratehaving an insulating surface and a second substrate having translucency,

[0019] each of the light emitting elements including: a first electrode;a layer containing an organic compound provided on the first electrodeso as to be in contact therewith; and a second electrode provided on thelayer containing the organic compound so as to be in contact therewith,

[0020] in which the terminal portion is placed on the first substrate soas to be positioned outside the second substrate; and

[0021] the first substrate and the second substrate are bonded to eachother through an adhesive in which plural kinds of conductive fineparticles having different diameters are mixed, whereas the secondelectrode and a wiring from the terminal portion are electricallyconnected to each other.

[0022] Further, another structure of the present invention relates to,as shown in an example of FIGS. 1A and 1B, a light emitting deviceincluding:

[0023] a pixel portion including a plurality of light emitting elements,a driving circuit and a terminal portion, between a first substratehaving an insulating surface and a second substrate having translucency,

[0024] each of the light emitting elements including: a first electrode;a layer containing an organic compound provided on the first electrodeso as to be in contact therewith; and a second electrode provided on thelayer containing the organic compound so as to be in contact therewith,

[0025] in which the terminal portion is placed on the first substrate soas to be positioned outside the second substrate; and

[0026] the first substrate and the second substrate are bonded to eachother through an adhesive in which a fine particle made of an inorganicmaterial and a conductive fine particle having a larger diameter thanthat of the fine particle are mixed, whereas the second electrode and awiring from the terminal portion are electrically connected to eachother.

[0027] Further, another structure of the present invention relates to,as shown in an example of FIGS. 2A and 2B, or FIGS. 3A and 3B, a lightemitting device including:

[0028] a pixel portion including a plurality of light emitting elements,each of the light emitting elements including: a first electrode; alayer containing an organic compound provided on the first electrode soas to be in contact therewith; and a second electrode provided on thelayer containing the organic compound so as to be in contact therewith;and

[0029] a terminal portion,

[0030] in which an end face of the layer containing the organic compoundis flush with that of the second electrode; and

[0031] there is a portion where the second electrode and a wiringextending from the terminal portion are electrically connected throughan adhesive containing a conductive fine particle, between the terminalportion and the pixel portion.

[0032] Further, another structure of the present invention relates to,as shown in an example of FIGS. 5A and 5B, a light emitting deviceincluding:

[0033] a pixel portion including a plurality of light emitting elements,each of the light emitting elements including: a first electrode; alayer containing an organic compound provided on the first electrode soas to be in contact therewith; and a second electrode provided on thelayer containing the organic compound so as to be in contact therewith;and

[0034] a terminal portion,

[0035] in which an end face of the layer containing the organic compoundis flush with that of the second electrode; and

[0036] there is a portion where the second electrode and a wiringextending from the terminal portion are connected through a thirdelectrode covering the second electrode, between the terminal portionand the pixel portion.

[0037] According to the above-mentioned structures of the presentinvention, the light emitting device is characterized in that the thirdelectrode is made of a metal. Further, according to the above-mentionedstructures, the second electrode and the third electrode are each one ofan anode and a cathode of the light emitting element.

[0038] Further, in each of the above-mentioned structures of the presentinvention, the second electrode has the same pattern form as that of thelayer containing the organic compound.

[0039] Further, in each of the above-mentioned structures of the presentinvention, the light emitting device is characterized in that the layercontaining the organic compound is made of a polymeric material.Alternatively, in each of the above-mentioned structures, the layercontaining the organic compound is a laminate layer composed of a layermade of a polymeric material and a layer made of a monomeric material.

[0040] Further, in each of the above-mentioned structures of the presentinvention, an end of the first electrode is covered with an insulator,and an upper end of the insulator includes a curved surface having afirst curvature radius whereas a lower end of the insulator includes acurved surface having a second curvature radius, the first and secondcurvature radii being 0.2 to 3 μm.

[0041] Further, in each of the above-mentioned structures of the presentinvention, the first electrode is made of a material havingtranslucency, and is one of an anode and a cathode of the light emittingelement.

[0042] Further, in each of the above-mentioned structures of the presentinvention, the layer containing the organic compound is made of amaterial emitting white light, and is combined with a color filter.Alternatively, the layer containing the organic compound is made of amaterial emitting monochromatic light, and is combined with one of acolor converting layer and a colored layer.

[0043] A structure of the present invention for realizing theabove-mentioned structures of the present invention relates to, as shownin an example of FIGS. 4A to 4C, a method of manufacturing a lightemitting device including a light emitting element having: an anode; alayer containing an organic compound in contact with the anode; and acathode in contact with the layer containing the organic compound,including:

[0044] forming a layer containing an organic compound, made of apolymeric material, by application on a first electrode havingtranslucency;

[0045] selectively forming a second electrode made of a metal on thefilm containing the organic compound by vapor deposition of heating avapor deposition material;

[0046] etching the layer containing the organic compound in aself-aligned manner by plasma etching using the second electrode as amask; and

[0047] selectively forming a third electrode made of a metal so as tocover the second electrode.

[0048] Further, in the structure of the present invention concerning amanufacturing method, the second electrode and the third electrode areeach one of an anode and a cathode. Also, according to theabove-mentioned structure concerning the manufacturing method, the thirdelectrode is formed by using any one of vapor deposition and sputtering.

[0049] Further, another structure of the invention concerning amanufacturing method relates to a method of manufacturing a lightemitting device including a light emitting element having: an anode; alayer containing an organic compound in contact with the anode; and acathode in contact with the layer containing the organic compound,including:

[0050] forming a layer containing an organic compound, made of apolymeric material, by application on a first electrode havingtranslucency;

[0051] selectively forming a second electrode made of a metal on thefilm containing the organic compound by vapor deposition of heating avapor deposition material;

[0052] etching the layer containing the organic compound in aself-aligned manner by plasma etching using the second electrode as amask; and

[0053] connecting the second electrode and a wiring extending from aterminal portion to each other through an adhesive containing aconductive particle.

[0054] Further, another structure of the invention concerning amanufacturing method relates to a method of manufacturing a lightemitting device including a light emitting element having: an anode; alayer containing an organic compound in contact with the anode; and acathode in contact with the layer containing the organic compound,including:

[0055] forming a thin film transistor on a first substrate;

[0056] forming a first electrode to be connected to the thin filmtransistor;

[0057] forming a layer containing an organic compound, made of apolymeric material, by application on the first electrode;

[0058] selectively forming a second electrode made of a metal on thefilm containing the organic compound by vapor deposition of heating avapor deposition material;

[0059] etching the layer containing the organic compound in aself-aligned manner by plasma etching using the second electrode as amask; and

[0060] connecting the second electrode and a wiring extending from aterminal portion to each other through an adhesive containing aconductive particle, while bonding the first substrate and the secondsubstrate to each other.

[0061] Further, in each of the above-mentioned structures concerning amanufacturing method, the manufacturing method is characterized in thatthe plasma is generated by exciting one or a plurality of gases selectedfrom the group consisting of: Ar, H, F and O.

[0062] Further, in each of the above-mentioned structures concerning amanufacturing method, the first electrode is one of an anode and acathode of the light emitting element electrically connected to a TFT.

[0063] Note that a light emitting element (EL element) has a layer,which contains an organic compound that provides luminescence(electroluminescence) when an electric field is applied (hereinafterreferred to as EL layer), and an anode and a cathode. Althoughluminescence obtained from organic compounds is classified into lightemission upon return to the base state from a singlet excitation(fluorescence), and light emission upon return to the base state from atriplet excitation (phosphorescence), it is possible to apply the lightemitting device manufactured according to the present invention whenusing either type of light emission.

[0064] Further, in the light emitting device of the present invention,the driving method of the screen display is not specifically limited,and other methods such as a dot sequential driving method, a linesequential driving method, an area sequential driving method, and thelike may also be used. Typically, there is adopted a line sequentialdriving method. Then, a typical line sequential driving method, a timedivision gradation driving method or an area gradation driving methodmay be used as appropriate. Further, the image signal inputted into thesource line of the light emitting device may be an analog signal or adigital signal. Combined with an image signal, driving circuit or thelike may be designed as appropriate.

[0065] Further, conductive paste may be performed with various coatingmethods (a screen printing method, a spin coating method, a dip coatingmethod, etc.). Among them, nano-metal ink can be formed with an inkjetmethod.

BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In the accompanying drawings:

[0067]FIGS. 1A and 1B are a top view and a cross-sectional view showingEmbodiment Mode 1, respectively;

[0068]FIGS. 2A and 2B are a top view and a cross-sectional view showingEmbodiment Mode 2, respectively;

[0069]FIGS. 3A and 3B are a top view and a cross-sectional view showingEmbodiment Mode 3, respectively;

[0070]FIGS. 4A to 4C are cross-sectional views showing etching steps ofEmbodiment Mode 4;

[0071]FIGS. 5A and 5B are a top view and a cross-sectional view showingEmbodiment Mode 4, respectively;

[0072]FIGS. 6A and 6B are a top view and a cross-sectional view showinga pixel of Embodiment 1, respectively;

[0073]FIGS. 7A to 7C are views showing manufacturing steps of Embodiment1;

[0074]FIGS. 8A and 8B are a top view and a cross-sectional view of anactive display device of Embodiment 1;

[0075]FIGS. 9A to 9C are views, each showing a laminate structure of alight emitting element in Embodiment 1;

[0076]FIGS. 10A to 10C are schematic views in the case where full-colordisplay is achieved by using the emission of white light in Embodiment1;

[0077]FIGS. 11A to 11D are schematic views in the case where full-colordisplay is achieved by using a laminate layer composed of a polymericmaterial and a monomeric material in Embodiment 1;

[0078]FIG. 12 is a diagram showing a manufacturing apparatus inEmbodiment 2;

[0079]FIGS. 13A to 13F, each showing an example of electronic appliancesin Embodiment 3;

[0080]FIGS. 14A to 14C, each showing an example of electronic appliancesin Embodiment 3;

[0081]FIG. 15 is a graph showing a transmittance of each of coloredlayers in Embodiment 1;

[0082]FIG. 16 is a graph showing a chromaticity coordinate of Embodiment1;

[0083]FIG. 17 is a photographic view showing a cross section of theperiphery of an insulator of Embodiment Mode 4;

[0084]FIG. 18 is a photographic view showing a cross section of theperiphery of an insulator of a comparative example;

[0085]FIGS. 19A to 19C are cross-sectional views of Embodiment 4;

[0086]FIG. 20 is a photographic view showing a cross section of theperiphery of an insulator;

[0087]FIGS. 21A to 21C are a top view and cross-sectional views showingEmbodiment Mode 4; and

[0088]FIGS. 22A and 22B are a top view and a cross-sectional viewshowing Embodiment Mode 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0089] Hereinafter, embodiment modes of the present invention will bedescribed with reference to the accompanying drawings.

[0090] (Embodiment Mode 1)

[0091]FIG. 1A is a top view showing an active-matrix light emittingdevice, and FIG. 1B is a cross-sectional view cut along a dotted lineX-X′ in FIG. 1A. In Embodiment Mode 1, a light emitting element 23having a laminate structure made of a polymeric material that emitswhite light is described as an example.

[0092] In FIGS. 1A and 1B, a pixel portion 12 and driving circuits(gate-side driving circuits 14 and 15 and a source-side driving circuit13) are formed on a substrate having an insulating surface. Each of thepixel portion 12 and the driving circuits 13 to 15 includes a pluralityof TFTs (not shown). Each of the TFTs formed in the pixel portion 12 isan element for controlling a current flowing to a layer 10 containing anorganic compound that emits light. A first electrode 19 or a powersupply line 16 is connected to the TFTs in the pixel portion 12.

[0093] In the pixel portion 12, a plurality of light emitting elements23 are placed; each of the light emitting elements 23 includes the firstelectrode 19, a second electrode 11 and a layer 10 containing an organiccompound interposed therebetween. Moreover, the first electrodes 19 tobe connected to each of the light emitting elements 23 are regularlyplaced in the pixel portion 12. The first electrode 19 is an anode (or acathode) of the organic light emitting element, whereas the secondelectrode 11 is a cathode (or an anode) of the organic light emittingelement. When a conductive material having translucency is used as thesecond electrode 11 and a metal is used as the first electrode 19, lightemitted from the light emitting element 23 can be transmitted through asealing material so as to be obtained therefrom. On the other hand, whena conductive material having translucency is used as the first electrode19 and a metal is used as the second electrode 11, light can be obtainedin an opposite direction. In the structure shown in FIGS. 1A and 1B,light can be obtained in either direction. In the case where lightemitted from the light emitting element 23 is transmitted through thesealing material so as to be obtained, the sealing material 20 and anadhesive 22 having electrical conductivity have indispensablytranslucency.

[0094] The layer 10 containing an organic compound has a laminatestructure. Typically, a laminate structure composed of: a hole transportlayer/a light emitting layer/an electron transport layer, which isformed on an anode, can be cited as an example. Since this structure hasan extremely high light emitting efficiency, most of the light emittingdevices currently under investigation and development apply thisstructure. Alternatively, a laminate structure composed of: a holeinjection layer/a hole transport layer/a light emitting layer/anelectron transport layer, or a laminate structure composed of: a holeinjection layer/a hole transport layer/a light emitting layer/anelectron transport layer/an electron injection layer may also be used.Moreover, the light emitting layer may be doped with a fluorescent dyeand the like. All these layers may be formed by using a monomericmaterial or by using a polymeric material. Throughout thisspecification, all the layers provided between the cathode and the anodeare collectively referred to as a layer containing an organic compound(electroluminescence (EL) layer). Therefore, the above-described holeinjection layer, hole transport layer, light emitting layer, electrontransport layer and electron injection layer are all fall within thecategory of the EL layer. The layer containing an organic compound (ELlayer) may contain an inorganic material such as silicon.

[0095] Both ends of the first electrode 19 and a portion between theends of the first electrodes 19 are covered with an organic insulator 18(also referred to as a barrier or a bank). Furthermore, the organicinsulator 18 may be covered with an organic insulating film.

[0096] A terminal electrode is formed in a terminal portion which has aconnection wiring 17 extending from the terminal electrode. Theconnection wiring 17 is electrically connected to the second electrode11 through the adhesive 22 having electrical conductivity. Since thelayer containing an organic compound is etched in a self-aligned mannerusing the second electrode 11 as a mask, an end face of the secondelectrode 11 and that of the layer 10 containing the organic compoundare flush with each other. The adhesive 22 having electricalconductivity is provided so as to be in contact with the end faces. Theconductive adhesive 22 contains a conductive fine particle 22 b such asa silver particle or a copper particle and a spacer 22 a. Furthermore,the sealing material 20 is adhered thereto so as to seal the lightemitting element 23. Either a thermosetting resin or an ultravioletcurable resin may be used as the adhesive 22 having electricalconductivity. In the case where a thermosetting resin is used as theadhesive 22 having electrical conductivity, it is necessary toappropriately select a material having such a baking temperature thatdoes not degrade the layer 10 containing an organic compound. In thecase where the ultraviolet curable resin is used, it is necessary to usea material having translucency as a sealing material.

[0097] The spacer 22 a may be made of an inorganic insulating material,an organic insulating material, or a combination thereof havingdifferent particle diameters. If an organic insulating film coated witha low-resistance metal film such as a gold film (for example, conductivefine particles obtained by uniformly gold-plating the surfaces ofplastic fine particles having a uniform particle diameter) is used asthe spacer 22 a, it can be said that the spacer 22 a serves as theconductive fine particle.

[0098]FIG. 1B shows an example where a diameter of the conductive fineparticle 22 b is larger than that of the spacer 22 a. Alternatively, anorganic material having elasticity coated with a metal film is used fora particle having a larger particle diameter, whereas an inorganicmaterial is used for a particle having a smaller diameter. Upon contactbonding of the sealing material 20, the particle having a largerdiameter is deformed so as to achieve the face contact. FIGS. 22A and22B show an example where a diameter of a conductive fine particle 1022b is smaller than that of a spacer 1022 a. In FIGS. 22A and 22B, it issufficient that the conductive fine particles 1022 b are present at ajunction between the second electrode 11 and the connection wiring 17for electrical connection. Therefore, it is not necessary to uniformlydistribute the conductive particles 1022 b in the adhesive 1022 havingelectrical conductivity; it is sufficient that the conductive particles1022 b are present in the vicinity of the second electrode 11 or theconnection wiring 17 at a high density due to gravity.

[0099] The use of the adhesive 22 having electrical conductivitysimultaneously allows the sealing of the light emitting element 23 byadhering the sealing material 20 and the electrical connection betweenthe connection wiring 17 and the second electrode 11, thereby improvinga throughput.

[0100] Although FIGS. 1A and 1B show the example where the adhesive 22having electrical conductivity is entirely formed over the pixelportion, the formation of the adhesive 22 is not limited thereto. Theadhesive 22 may also be formed in a partial manner. Also, the adhesive22 may be a laminate of a material layer containing a conductive fineparticle such as a silver paste, a copper paste, a gold paste or a Pdpaste and an adhesive containing a spacer or a filler. In the case wherethe adhesive 22 has such a laminate structure, the connection wiring 17and the second electrode 11 are first electrically connected to eachother by forming the material layer containing a conductive fineparticle. Thereafter, the sealing material 20 is adhered by using anadhesive containing a spacer or a filler to seal the light emittingelement 23.

[0101] The sealing material 20 is bonded by a spacer or a filler so asto maintain a distance of about 2 to 30 μm. In this manner, all thelight emitting elements are closely sealed. Although not shown in thedrawings, a concave portion is formed in the sealing material 20 bysandblasting or the like. A desiccant is placed in the concave portion.It is preferred to perform the degassing by annealing in vacuum,immediately before the adhesion of the sealing material 20. Moreover, itis preferred to bond the sealing material 20 under an ambient containingan inert gas (a rare gas or nitrogen).

[0102] In the case where an electrical resistivity of the adhesive 22having electrical conductivity is relatively high, the electrode isformed on the sealing material 20 in advance. Then, upon bonding, theelectrode is electrically connected to the adhesive 22 having electricalconductivity so as to lower the resistance. In this case, it ispreferred to use an inorganic insulating material coated with alow-resistance metal film such as gold, as the spacer 22 a. Thus, it ispossible to maintain a distance between the sealing material 20 and thesecond electrode 11 with a particle diameter of the spacer 22 a as wellas to permit the electrical connection between the second electrode 11and the electrode on the sealing material 20 and the electricalconnection between the connection wiring 17 and the electrode on thesealing material 20. In the case where a plurality of kinds of particleshaving different diameters are used, an organic material havingelasticity is used for a particle having a larger diameter, whereas aninorganic material is used for a particle having a smaller diameter.Upon contact bonding of the sealing material 20, the particle having alarger diameter is deformed so as to achieve the face contact with theelectrode on the sealing material 20.

[0103] (Embodiment Mode 2)

[0104]FIGS. 2A and 2B show an example of a structure different from thatshown in FIGS. 1A and 1B, where an adhesive having electricalconductivity is formed on a large area. For the purpose ofsimplification, the same components as those in FIGS. 1A and 1B aredenoted by the same reference numerals in FIGS. 2A and 2B. Since thecomponents up to the second electrode 11 in FIGS. 2A and 2B are the sameas those in FIGS. 1A and 1B, the detailed description thereof is hereinomitted.

[0105] In Embodiment Mode 2, an example where a conductive material 32is partially formed and a sealer 31 is separately formed is shown. Theconnection wiring 17 and the second electrode 11 are electricallyconnected to each other through the conductive material 32. Since thelayer 10 containing an organic compound is etched in a self-alignedmanner using the second electrode 11 as a mask, the end face of thesecond electrode 11 is flush with that of the layer 10 containing anorganic compound. The conductive material 32 is provided so as to be incontact with the end faces.

[0106] In FIGS. 2A and 2B, as the conductive material 32, a conductivepaste as is represented by a silver paste or a copper paste, aconductive ink, or a nanometal ink (an independently dispersed ultrafineparticle dispersion solution, in which Ag, Au or Pd having a particlediameter of 5 to 10 nm is dispersed at a high density withoutaggregation) is used. For example, a conductive material containing asilver-plated copper powder, a phenol resin, dimethylene glycolmonomethyl ether and the like as a main component and having a specificresistance of 5×10⁻⁴ Ω·cm or less and an adhesive strength of 0.8 kg/mm²or higher may be used as the conductive material 32. Alternatively, aquick-drying silver type conductive agent (a modified polyolefin resincontaining a flat-shaped silver powder having a particle diameter of 0.5to 1 μm) may also be used as the conductive material 32.

[0107] In the case where a solvent is used as the conductive material32, there is concern that a vapor might be generated due to heat,thereby contaminating the layer containing an organic compound. In orderto cope with this problem, the sealer 31 is provided between theconductive material 32 and the pixel portion 12 so as to prevent thelayer 10 containing an organic compound from being contaminated in thepresent invention. Therefore, it is preferred to form the conductivematerial 32 after the sealer 31 is formed to be adhered to the sealingmaterial 20. The order of formation of the sealer 31 and the conductivematerial 32 is not specially limited. Instead of the above-describedorder, after formation of the conductive material 32, the sealer 31 maybe formed to be adhered to the sealing material 20.

[0108] The sealer 31 contains a filler mixed therein. The filler servesto bond the sealing material 20 while keeping an even distance.Moreover, a spacer may be mixed therein in addition to the filler. Thesealer 31 may also be formed to partially overlap the gate-side drivingcircuits 14 and 15 as shown in FIG. 2A.

[0109] Light emitted from the light emitting element 23 can be obtainedin either direction in the structure shown in FIGS. 2A and 2B. Moreover,it is essential for the sealing material 20 to have translucency in thecase where light emitted from the light emitting element 23 istransmitted through the light emitting material so as to be obtained.

[0110] Embodiment Mode 2 can be freely combined with Embodiment Mode 1.

[0111] (Embodiment Mode 3)

[0112]FIGS. 3A and 3B show an example of a structure different fromthose shown in FIGS. 1A and 1B, and FIGS. 2A and 2B, in which thesealing material is bonded. For the purpose of simplification, the samecomponents as those in FIGS. 1A and 1B are denoted by the same referencenumerals in FIGS. 3A and 3B. Since the components up to the secondelectrode 11 in FIGS. 3A and 3B are the same as those in FIGS. 1A and1B, the detailed description thereof is herein omitted.

[0113] In Embodiment Mode 3, an example where a conductive material 42is partially formed and sealing is conducted using a protective film 41is shown. The connection wiring 17 and the second electrode 11 areelectrically connected to each other through the conductive material 42.Since the layer 10 containing an organic compound is etched in aself-aligned manner using the second electrode 11 as a mask, the endface of the second electrode 11 is flush with that of the layer 10containing an organic compound. The conductive material 42 is providedso as to be in contact with the end faces.

[0114] Similarly to the conductive material 32 described in theabove-described Embodiment Mode 2, a conductive paste as is representedby a silver paste or a copper paste, or a conductive ink is used as aconductive material 42 shown in FIGS. 3A and 3B. Alternatively, ananometal ink (an independently dispersed ultrafine particle dispersionsolution in which Ag, Au or Pd having a particle diameter of 5 to 10 nmis dispersed at a high density without aggregation) may also be used asthe conductive material 42. The nanometal ink is baked at 220 to 250° C.

[0115] After formation of the conductive material 42, a protective film41 is formed. As the protective film 41, an insulating film containingsilicon nitride or silicon oxynitride as a main component obtained bysputtering (a DC method or an RF method) or a thin film containingcarbon as a main component obtained by a PCVD method is used. A siliconnitride film can be obtained when the film formation is conducted in anambient containing nitrogen and argon, using a silicon target.Alternatively, a silicon nitride target may be used instead. Theprotective film 41 may also be formed by using a film formationapparatus using a remote plasma. In the case where emitted light is tobe transmitted through the protective film, it is preferred that athickness of the protective film is as thin as possible.

[0116] In the present invention, the thin film containing carbon as amain component is characterized by being a DLC (Diamond Like Carbon)film having a thickness of 3 to 50 nm. The DLC film has a SP³ bond as abond between carbon atoms in terms of short-distance order as well as anamorphous structure at the macroscopic level. As a composition of theDLC film, the DLC film contains carbon at 70 to 95 atm % and hydrogen at5 to 30 atm %. The DLC film is extremely hard and excellent ininsulation properties. Moreover, such a DLC film is characterized by itslow gas permeability to a vapor, oxygen or the like. Moreover, it isknown that this film has a hardness of 15 to 25 GPa on the basis ofmeasurement by a microhardness tester.

[0117] The DLC film can be formed by a plasma CVD method (typically, anRF plasma CVD method, a microwave CVD method, an electron cyclotronresonance (ECR) CVD method and the like), sputtering or the like. Withany of the film formation methods, the DCL film can be formed with goodadherence. The DLC film is formed while the substrate is being placed ona cathode. Alternatively, a negative bias is applied so that a fine andhard film can be formed by utilizing ion impact to a certain degree.

[0118] As a reactive gas used for film formation, a hydrogen gas and ahydrocarbon type gas (for example, CH₄, C₂H₂, C₆H₆ or the like) is used.The reactive gas is then ionized by glow discharge. The obtained ionsare accelerated to collide against a negatively self-biased cathode soas to form the DLC film. As a result, a fine and smooth DLC film can beobtained. The obtained DLC film is an insulating film which istransparent or semitransparent to visible light. Throughout thisspecification, the sentence “transparent to visible light” means that atransmittance of visible light is 80 to 100%, and the sentence“semitransparent to visible light” means that a transmittance of visiblelight is 50 to 80%.

[0119] In the case where a silicon nitride film is formed by sputteringso as to be in contact with a film formed of a transparent conductivefilm, there is a possibility that an impurity (In, Sn, Zn or the like)contained in the transparent conductive film may enter the siliconnitride film so as to be mixed therein. In this case, it is possible toprevent the impurity from entering the silicon nitride film by forming asilicon oxide film serving as a buffer layer between the transparentconductive film and the silicon nitride film. The formation of thebuffer layer having the above structure prevents the impurity fromentering the transparent conductive film so that an excellent protectivefilm containing no impurity can be formed.

[0120] Moreover, after formation of the protective film, a sealer may beformed so as to be bonded to the sealing material for enhancedsealability.

[0121] Embodiment Mode 3 can be freely combined with any one ofEmbodiment Modes 1 and 2.

[0122] (Embodiment Mode 4)

[0123] Herein, a forming process of a light emitting element is simplyexplained below with reference to FIGS. 4A, 4B, and 4C. For the purposeof simplification, the same components as those in FIGS. 1A and 1B aredenoted by the same reference numerals in FIGS. 4A, 4B, and 4C.

[0124] First, after forming a TFT (not shown herein), the firstelectrode 19, the connection wiring 17 and the insulator 18 on asubstrate, a layer 10 containing an organic compound is formed byapplication utilizing spin coating. Thereafter, the layer 10 containingthe organic film is baked by heating under vacuum (FIG. 4A). In the caseof the layer 10 containing an organic compound is formed to have alaminate structure, the film formation and the baking may be repeated.

[0125] Next, the second electrode 11 made of a metal is selectivelyformed by vapor deposition using a vapor deposition mask 50 (FIG. 4B).Although FIG. 4B shows an example where the vapor deposition isperformed with a distance between the metal mask and the layer 10containing an organic compound, the vapor deposition may be performedwhile the metal mask and the layer containing the organic compound arebeing in contact with each other.

[0126] Next, the layer 10 containing an organic compound is etched in aself-aligned manner using the second electrode 11 as a mask. In thiscase, selective etching is performed using a plasma generated byexciting one or a plurality of kinds of gases selected from the groupconsisting of Ar, H, F and O (FIG. 4C). Herein, it is important toappropriately select a material or a thickness of the second electrode11 so that the second electrode 11 is resistant to a plasma. The presentinvention allows the selective formation of the polymeric material layerso as to easily form a structure, in which the layer containing anorganic compound is not formed at a junction of the wiring to beconnected to an external power source.

[0127] A state shown in FIG. 4C is obtained by the steps so far. In thisstate, however, the second electrode is not connected to any point, andtherefore is in a floating state. Thus, in the later step, the secondelectrode 11 is electrically connected to the connection wiring 17. As amethod for electrically connecting the second electrode 11 to theconnection wiring 17, the adhesive 22 having electrical conductivityshown in the above Embodiment Model may be used. Alternatively, theconductive materials 32 and 42 respectively described in EmbodimentModes 2 and 3 above may be used.

[0128] In Embodiment Mode 4, a third electrode 51 made of alow-resistant metal is formed as a method for electrically connectingthe second electrode 11 to the connection wiring 17 (FIG. 5B). A topview of a structure fabricated by the steps so far is shown in FIG. 5A.

[0129] The third electrode 51 may be appropriately formed by sputtering,vapor deposition or PCVD. Moreover, it is preferred to use a metalhaving a lower electrical resistivity than that of a material of thesecond electrode 11, for the third electrode 51. As the third electrode51, for example, a film containing, as a main component, an elementselected from the group consisting of: poly-Si, W, WSi_(x), Al, Ti, Mo,Cu, Ta, Cr and Mo, which is doped with an impurity element for impartingan electrical conductivity type, a film made of an alloy material or acompound material containing the above-described element as a maincomponent, or a laminate film thereof is used. In this case, anelectrode made of a laminate layer (specifically, a laminate of TiN, Aland TiN) including a nitride layer or a fluoride layer as the uppermostlayer is used as the third electrode 51. Therefore, light emitted fromthe light emitting element can be transmitted through the firstelectrode 19 so as to be obtained.

[0130] Moreover, the same material as that of the second electrode 11may be used for the third electrode 51. In such a case, it is preferablethat a thickness of the third electrode 51 is set larger than that ofthe second electrode 11 so as to reduce the resistance. Furthermore, inthe case where the same material as that of the second electrode 11 isused for the third electrode 51, a thickness of the second electrode 11can be further reduced.

[0131] As the step after formation of the third electrode 51, the lightemitting element may be sealed by forming a protective film or adheringa sealing material thereto.

[0132] Hereinafter, a cross-sectional shape of the insulator 18 made ofan organic material shown in FIG. 5B will be described because it isimportant. In the case where an organic compound film is to be formed onthe insulator 18 by application or a metal film serving as a cathode isto be formed by vapor deposition, if a lower end or an upper end of theinsulator 18 does not have a curved surface, poor film formation occursas shown in FIG. 18 where a convex portion is formed on the upper end ofthe insulator 18. Therefore, in the present invention, the upper end ofthe insulator 18 has a curved surface having a first curvature radius,whereas the lower end of the insulator 18 has a curved surface having asecond curvature radius, as shown in FIGS. 17 and 5B. It is preferredthat both the first and second curvature radii are 0.2 to 3 μm. With thepresent invention, good coverage for the organic compound film or themetal film can be obtained. Moreover, a defect called shrink, i.e.,reduction of a light emitting area, can be decreased. Furthermore, theshrink can be reduced by forming a silicon nitride film or a siliconoxynitride film on the insulator 18. A taper angle on the side face ofthe insulator 18 may be set at 45°±10°.

[0133] As the insulator 18, an inorganic material (silicon oxide,silicon nitride, silicon oxynitride or the like), a photosensitive ornon-photosensitive organic material (polyimide, acrylic, polyamide,polyimide amide, a resist or benzocyclobutene), or a laminate thereofcan be used. In the case where the insulator 18 is desired to include acurved surface having a first curvature radius at its upper end and acurved surface having a second curvature radius at its lower end asshown in FIGS. 17 and 5B, the formation is facilitated by the use of aphotosensitive organic material. Moreover, either a photosensitivenegative type material, which is rendered insoluble to an etchant bylight, or a photosensitive positive type material, which is renderedsoluble to an etchant by light, may be used as the insulator 18.

[0134]FIGS. 21A and 21C show an example where a protective film 70 madeof a silicon nitride film is formed on an insulator 68 and a pattern ofthe insulator is different from that of the silicon nitride film. Forsimplification, FIG. 21A shows a top view at the stage where thecomponents up to a layer 60 containing an organic component are formed;FIG. 21B shows a cross-sectional view cut along a line A-A′ in FIG. 21A;and FIG. 21C shows a cross-sectional view cut along a line B-B′ in FIG.21A. In the cross-sectional view shown in FIG. 21B, the insulator 68 isnot present between adjacent first electrodes 69. In FIG. 21A, theinsulator 68 has a stripe-shaped pattern. The silicon nitride filmserving as the protective film 70 has a grid pattern as is indicatedwith a dotted line, which covers only ends of each of the firstelectrodes 69. With the insulator 68 having a stripe-shaped pattern, itis possible to more easily remove a particle or an impurity in wetcleaning of a surface of the first electrode 69, than with the insulatorhaving a grid pattern. In FIGS. 21A to 21C, a part of a pixel portion62, which is not covered with the protective film 70, functions as alight emitting region.

[0135] Instead of using the silicon nitride film, a silicon oxynitridefilm or a film represented by AlN_(X)O_(Y) may be used as the protectivefilm 70. The film represented by AlN_(X)O_(Y) may be formed whileintroducing oxygen, nitrogen or a rare gas from a gas introductionsystem, by sputtering using a target made of AlN or Al. It is sufficientfor the layer represented by AlN_(X)O_(Y) to contain nitrogen at severalatm % or higher, preferably, 2.5 atm % to 47.5 atm %, and oxygen at 47.5atm % or lower, preferably, 0.01 to less than 20 atm %.

[0136] By forming the protective film 70 on the insulator 68, it ispossible to improve the evenness in film thickness of the layer 60containing an organic compound. Therefore, heat generation due toelectric field concentration caused upon light emission can berestrained. As a result, the degradation of the light emitting elementas is represented by shrink, i.e., reduction in light emitting area, canbe prevented.

[0137] Embodiment Mode 4 can be freely combined with any one ofEmbodiment Modes 1 to 3.

[0138] The present invention having the above-described structure willbe described in further detail by embodiments described below.

[0139] (Embodiments)

[0140] [Embodiment 1]

[0141] In this embodiment, a structure, in which light emitted from anEL element is transmitted through an element substrate so as to bereflected onto viewer's eyes, will be described below. In this case, aviewer can recognize an image from the element substrate side.

[0142] First, a pixel structure, in which three TFTs are placed for onepixel, will be described. FIG. 6A shows an example of a top view showinga pixel in detail.

[0143] The structure shown in FIG. 6A includes a TFT 606 for erasing inthe case where SES driving is to be performed. A gate electrode of theTFT 606 and a second gate signal line 603 for inputting a signal forerasing are connected to each other. A source electrode and a powersupply line 604 are connected to each other. A drain electrode isconnected to a drain electrode of a TFT 605 for switching and a gateelectrode of a TFT 607 for driving.

[0144] In the case of three-transistor type, two TFTs, that is, the TFT605 for switching and the TFT 606 for erasing are horizontally placed ina linear manner between the first gate signal line 602 and the secondgate signal line 603. A drain region of the TFT 605 for switching and adrain region of the TFT 606 for erasing may overlap each other. At thistime, a point where a source region of the TFT 605 for switching ispresent, a point where a drain region thereof is present, a point wherea source region of the TFT 606 for erasing is present, and a point wherea drain region thereof is present are placed so as to be arranged on asingle straight line.

[0145] With the arrangement as described above, an aperture ratio can beincreased so as to provide an opening in a simple shape.

[0146]FIG. 6B shows a cross section cut along a line á-á′ in FIG. 6A. Asemiconductor layer 614 may be longitudinally meandered as is the TFT607 for driving. With such a shape of the semiconductor layer 614, it ispossible to increase a channel length L of the TFT 607 for drivingwithout decreasing an aperture ratio. In order to lower an OFF currentvalue, the TFT 607 for driving may be a TFT having a plurality ofchannels. It is preferred that the channel length L of the TFT 607 fordriving is 100 μm or more. In the case where the channel length L isincreased, an oxide film capacitance C_(OX) is correspondinglyincreased. Therefore, it is possible to use a part of the capacitance asa storage capacitor for an organic light emitting element.Conventionally, in order to form a storage capacitor for each pixel, aspace for forming the storage capacitor is additionally required,Furthermore, a capacitor line, a capacitor electrode and the like areprovided. With the pixel structure of the present invention, however,the formation of the capacitor line or the capacitor electrode can beomitted. Moreover, in the case where a storage capacitor is formed byusing the oxide film capacitance C_(OX), the storage capacitor is formedby a gate electrode using a gate insulating film as a dielectric and asemiconductor (channel formation region) overlapping the gate electrodethrough the gate insulating film. Therefore, even if the channel lengthof the TFT is increased, the pixel can be designed without decreasingthe aperture ratio as long as the semiconductor layer of the TFT 607 fordriving, which is connected to a pixel electrode 608, is placed underthe power supply line 604 or the source signal line 601 placed as anupper layer on the gate electrode. More specifically, with the pixelstructure as shown in FIGS. 6A and 6B, a sufficient storage capacitorcan be provided even if a space for forming the capacitor electrode orthe capacitor wiring is omitted, thereby further increasing the apertureratio. Furthermore, in the case where the channel length L is increased,variation in electrical properties among TFTs can be reduced even if avariation occurs in a TFT manufacturing process such as in anirradiation condition of laser light.

[0147]FIGS. 8A and 8B show an exterior appearance of an active-matrixlight emitting device. FIG. 8A is a top view showing an active-matrixlight emitting device, and FIG. 8B is a cross-sectional view cut along aline A-A′ in FIG. 8A. The active-matrix light emitting device includes asource-side driving circuit 901, a pixel portion 902, and a gate-sidedriving circuit 903, each being indicated with a dotted line. Thereference numeral 904 indicates a sealing substrate, and the referencenumeral 905 indicates a sealing agent. The interior surrounded by thesealing agent 905 forms a space 907.

[0148] A wiring 908 serves to transmit a signal to be input to thesource-side driving circuit 901 and the gate-side driving circuit 903,and receives a video signal or a clock signal from a flexible printcircuit (FPC ; terminal portion) 909 serving as an external inputterminal. Although the FPC (terminal portion) alone is shown, a printedwiring board (PWB) may be attached to the FPC (terminal portion). Thelight emitting device in this specification includes not only a mainbody of the light emitting device but also the FPC (terminal portion) orthe PWB attached thereto.

[0149] Next, a cross-sectional structure will be described withreference to FIG. 8B. Although driving circuits and a pixel portion areformed on the substrate 910, the source-side driving circuit 901 as adriving circuit and the pixel portion 902 are shown.

[0150] As the source-side driving circuit 901, a CMOS circuit, in whichan n-channel TFT 923 and a p-channel TFT 924 are combined with eachother, is formed. Each of TFTs forming the driving circuit may be formedby a known CMOS circuit, PMOS circuit or NMOS circuit. Although adriver-integrated type light emitting device, in which a driving circuitis formed on a substrate, is shown in this embodiment, this structure isnot necessarily required. Alternatively, a driving circuit may be formedin the exterior, not on the substrate.

[0151] The pixel portion 902 is formed by a plurality of pixels, eachincluding the TFT 911 for switching, a TFT 912 for current control, anda first electrode (anode) 913 electrically connected to a drain of theTFT 912 for current control.

[0152] Insulators 914 are formed on both ends of the first electrode(anode) 913. On the first electrode (anode) 913, a layer 915 containingan organic compound is formed. On the layer 915 containing an organiccompound, a second electrode (cathode) 916 having the same pattern shapeas that of the layer 915 containing an organic compound and having anend being flush with that of the layer 915 is formed. As a result, alight emitting element 918 composed of the first electrode (anode) 913,the layer 915 containing an organic compound, and the second electrode(cathode) 916 is formed. Since the light emitting element 918 emitswhite light in this example, a color filter (not shown forsimplification) composed of a colored layer and BM is provided on thesubstrate 910.

[0153] For electrical connection between the second electrode 916 andthe wiring 908, a third electrode 917 shown in Embodiment Mode 4 isformed in this embodiment. The third electrode 917, which is in contactwith the second electrode 916 and the wiring 908, functions as a commonwiring for all pixels. The third electrode 917 is electrically connectedto the FPC (terminal portion) 909 via the wiring 908.

[0154] In order to seal the light emitting element 918 formed on thesubstrate 910, a sealing substrate 904 is attached to a sealing agent905. In order to hold a distance between the sealing substrate 904 andthe light emitting element 918, a spacer made of a resin film may alsobe provided. The space 907 inside the sealing agent 905 is filled withan inert gas such as nitrogen. It is preferred to use an epoxy typeresin as the sealing agent 905. Moreover, it is desirable that thesealing agent 905 does not allow moisture or oxygen to be permeatedtherethrough as much as possible. Furthermore, the interior of the space907 may contain a substance having the effect of absorbing oxygen orwater.

[0155] In addition to a glass substrate or a quartz substrate, a plasticsubstrate made of FRP (Fiberglass-Reinforced Plastics), PVF (polyvinylfluoride), Mylar, polyester, acrylic or the like can also be used as amaterial constituting the sealing substrate 904 in this embodiment.Moreover, after bonding the sealing substrate 904 by using the sealingagent 905, it is possible to seal with a sealing agent so as to coverits side face (exposed face).

[0156] By sealing the light emitting element within the space 907 in amanner as described above, the light emitting element can be completelyblocked from the exterior. Therefore, a substrate accelerating thedegradation of the layer containing an organic component such asmoisture or oxygen can be prevented from entering from the exterior.Accordingly, a highly reliable light emitting device can be obtained.

[0157] An example of a manufacturing process of the above-describedstructure is shown in FIGS. 7A to 7C.

[0158]FIG. 7A is a cross-sectional view at the stage where a secondelectrode (a cathode made of Li-Al) is selectively formed by using avapor deposition mask after formation of an organic compound film (alaminate layer containing PEDOT) by application. For simplification, amethod for manufacturing an anode made of a transparent conductive filmor a TFT is herein omitted.

[0159] Next, FIG. 7B is a cross-sectional view at the stage where theorganic compound film (the laminate layer containing PEDOT) is etched ina self-aligned manner by a plasma using the second electrode as a mask.

[0160] Next, FIG. 7C is a cross-sectional view at the stage where athird electrode to be connected to a connection wiring is selectivelyformed. The second electrode and the third electrode may be formed ofthe same material, or a material of the third electrode may have a lowerelectrical resistivity than that of the second electrode.

[0161] This embodiment shows an example of a method with a combinationof a white-light emitting element and a color filter (hereinafter, thismethod is referred to as a color filter method). Hereinafter, a methodfor forming a white-light emitting element so as to obtain full-colordisplay will be described with reference to FIG. 10A.

[0162] According to a color filter method, a light emitting elementincluding an organic compound film emitting white light is formed, sothat the emitted white light is transmitted through a color filter so asto obtain emission of red, green and blue light.

[0163] Although there are various methods for obtaining the emission ofwhite light, the case of using a light emitting layer made of apolymeric material, which can be formed by application, will bedescribed herein. In this case, dye doping to a polymeric materialserving as a light emitting layer can be performed by adjusting asolution. The emission of white light can be extremely easily obtainedas compared with a vapor deposition method of performing co-depositionfor doping a plurality of dyes.

[0164] Specifically, after forming of a film containing poly(ethylenedioxythiophene) (PEDOT) by application and baking of a poly(ethylenedioxythiophene)/poly(styrene sulfonic acid) solution (PEDOT/PSS) actingas a hole injection layer on the entire surface of an anode made of ametal having a large work function (Pt, Cr, W, Ni, Zn, Sn, In), aluminescence center dye (1,1,4,4-tetraphenyl-1,3-butadiene (TPB),4-dicyanomethylene-2-methyl-6(p-dimethylamino-styryl)-4H-pyran (DCM1),Nile Red, coumarin 6 or the like) acting as a light emitting layer dopedwith polyvinyl carbazole (PVK) is applied on the entire surface and thenis baked. Thereafter, a cathode made of a laminate layer composed of: athin film containing a metal having a small work function (Li, Mg orCs); and a transparent conductive film (ITO (an alloy of indium oxideand tin oxide), an alloy of indium oxide and zinc oxide (In₂O₃—ZnO),zinc oxide (ZnO) and the like) deposited thereon is formed. PEDOT/PSSuses water as a solvent and is not soluble to an organic solvent.Therefore, even if PVK is to be applied thereon, there is no possibilitythat PEDOT/PSS might be dissolved again therein. Moreover, sincePEDOT/PSS and PVK use respectively different solvents, it is preferrednot to use the same film formation chamber.

[0165] Although the example where the layer containing an organiccompound is constituted as a laminate layer is described as illustratedin FIG. 9B, the layer containing an organic compound may be constitutedas a single layer as shown in FIG. 9A. For example, 1, 3, 4-oxadiazolederivative (PBD) having electron transportability may be dispersed inpolyvinyl carbazole (PVK) having hole transportability. Moreover, PBD isdispersed at 30 wt % as an electron transport agent, and an appropriateamount of four kinds of dyes (TPB, coumarin 6, DCM1 and Nile Red) isdispersed, thereby obtaining the emission of white light.

[0166] The organic compound film is formed between the anode and thecathode. In this structure, holes injected from the anode and electronsinjected from the cathode are rebonded to each other in the organiccompound film, whereby white light emission can be obtained in theorganic compound film.

[0167] Alternatively, it is possible to appropriately select an organiccompound film emitting red light, an organic compound film emittinggreen light or an organic compound film emitting blue light so as tocombine them for mixing the colors; in this manner, when viewed as awhole, the emission of white light can be obtained.

[0168] The organic compound film formed in the above-described mannerallows the emission of white light to be obtained when viewed as awhole.

[0169] By forming a color filter including a colored layer (R) forabsorbing light other than red light, a colored layer (G) for absorbinglight other than green light, and a colored layer (B) for absorbinglight other than blue light in a direction in which the organic compoundfilm emits white light, the white light emitted from the light emittingelement can be separated into red light, green light and blue light. Inthe case of an active-matrix light emitting device, TFTs are formedbetween the substrate and the color filter.

[0170] For the colored layers (R, G, B), in addition to the simpleststriped pattern, an oblique tessellated arrangement, a triangulartessellated arrangement, an RGBG quadruple-pixel arrangement, or an RGBWquadruple-pixel arrangement can be used.

[0171]FIG. 15 shows an example of a relation between a transmittance ofeach colored layer and a wavelength by using a white light source (D65).Each of the colored layers constituting the color filter is formed by acolor resist made of an organic photosensitive material in which apigment is dispersed. FIG. 16 shows a color reproducibility range as achromaticity coordinate in the case where white light emission and thecolor filter are combined. A chromaticity coordinate of white lightemission is represented by (x, y)=(0.34, 0.35). It is understood fromFIG. 16 that the color reproducibility as full color display can besufficiently ensured.

[0172] Since all the organic compound films are constituted to emitwhite light even if the thus obtained colors of light are different inthis case, it is not necessary to separately color the organic compoundfilms for the respective colors of light. Moreover, a circularpolarizing plate for preventing the mirror reflection is notparticularly required.

[0173] Next, a CCM (color changing medium) method, which is realized bycombining a blue-light emitting element having an organic compound filmfor emitting blue light with a fluorescent color conversion layer, willbe described with reference to FIG. 10B.

[0174] According to the CCM method, fluorescent color conversion layersare excited by blue light emitted from a blue-light emitting element soas to convert the color by each of the color conversion layers.Specifically, the emission of red light, green light and blue light isobtained by converting blue light into red light (B→R) in one colorconversion layer, converting blue light into green light (B→G) in onecolor conversion layer, and converting blue light into blue light (B→B)in one color conversion layer, respectively (the conversion of bluelight into blue light can be omitted). Also in the case of the CCMmethod, TFTs are formed between the substrate and the color conversionlayer in the active-matrix light emitting device.

[0175] Also in this case, it is not necessary to form separately coloredorganic compound films. Moreover, a circular polarizing plate forpreventing the mirror reflection is not particularly required.

[0176] In the case where the CCM method is employed, since the colorconversion layers are fluorescent, the color conversion layers areexcited by external light to disadvantageously lower the contrast. Thus,as shown in FIG. 10C, it is suitable to enhance the contrast byattaching a color filter or the like thereon. Note that, FIG. 10C showsan example in which a white color-light emitting device is used,however, monochromatic light emitting device can be used.

[0177] Alternatively, as shown in FIG. 9C, the emission of white lightcan be obtained by laminating a layer made of a polymeric material and alayer made of a monomeric material as the layer containing an organiccompound. In the case the emission of white light is to be obtained by alaminate layer, after forming a layer made of a polymeric materialserving as a hole injection layer by application, co-deposition may beperformed by vapor deposition so as to dope a dye, which emits light ofa different color from that of a light emitting region, into a holetransport layer, thereby mixing the color of the dye with the color oflight emitted from the light emitting region. By appropriately adjustinga material of the light emitting layer or the hole transport layer, theemission of white light can be obtained when viewed as a whole.

[0178] Moreover, according to the present invention, the layercontaining an organic compound made of a polymeric material is etched ina self-aligned manner by a plasma using an electrode as a mask. Thepresent invention is applicable not only to a white-light emittingelement but also to a colored-light emitting element including at leastone layer made of a polymeric material as the layer containing anorganic compound.

[0179]FIGS. 11A to 11D show an example of a laminate structure of alight emitting element.

[0180] A laminate structure shown in FIG. 11A includes, on an anode 701,an layer 702 containing an organic compound composed of a first organiclayer 702 a made of a polymeric material, a second organic layer 702 bmade of a monomeric material, and a cathode buffer layer 703. Byappropriately setting materials and thicknesses of these layersinterposed between the cathode and the anode, a red-, green- orblue-light emitting element can be obtained.

[0181] In the case where a red-light emitting element is to be obtained,as shown in FIG. 11B, a polymeric material PEDOT/PSS is applied on ananode made of ITO by spin coating, and then is baked under vacuum so asto obtain a film containing PEDOT whit a thickness of 30 nm. Next, a4,4′-bis[N-(1-naphtyl)-N-phenyl-amino]-biphenyl (hereinafter, referredto as á-NPD) film is formed by vapor deposition to have a thickness of60 nm. Next, a tris(8-quinolinolato)aluminum (hereinafter, referred toas Alq₃) film containing DCM is formed as a dopant by vapor depositionto have a thickness of 40 nm. Next, a film of Alq₃ is formed to have athickness of 40 nm. Then, a CaF₂ film is formed by vapor deposition tohave a thickness of 1 nm. As the final step, an Al film is formed tohave a thickness of 200 nm by sputtering or vapor deposition to completea red-light emitting element.

[0182] In the case where a green-light emitting element is to beobtained, as shown in FIG. 11C, a polymeric material PEDOT/PSS isapplied on an anode made of ITO by spin coating, and then is baked undervacuum so as to obtain a film containing PEDOT whit a thickness of 30nm. Next, an á-NPD film is formed by vapor deposition to have athickness of 60 nm. Next, an Alq₃ film containing DMQD is formed as adopant by vapor deposition to have a thickness of 40 nm. Next, a film ofAlq₃ is formed to have a thickness of 40 nm. Then, a CaF₂ film is formedby vapor deposition to have a thickness of 1 nm. As the final step, anAl film is formed to have a thickness of 200 nm by sputtering or vapordeposition to complete a green-light emitting element.

[0183] In the case where a blue-light emitting element is to beobtained, as shown in FIG. 11D, a polymeric material PEDOT/PSS isapplied on an anode made of ITO by spin coating, and then is baked undervacuum so as to obtain a thickness of 30 nm. Next, an á-NPD film isformed by vapor deposition to have a thickness of 60 nm. Next, abasocuproine (hereinafter, referred to as BCP) film is formed as adopant to have a thickness of 10 nm. Next, a film of Alq₃ is formed tohave a thickness of 40 nm. Then, a CaF₂ film is formed by vapordeposition to have a thickness of 1 nm. As the final step, an Al film isformed to have a thickness of 200 nm by sputtering or vapor depositionto complete a blue-light emitting element.

[0184] In the case where the above-described colored light emittingelements (R, G, B) are to be formed, it is not necessary to provide acolor filter. However, a color filter may be additionally provided toincrease the color purity.

[0185] Moreover, Embodiment 1 may be combined with any one of EmbodimentModes 1 to 4.

[0186] [Embodiment 2]

[0187] In Embodiment 2, an example of a multi-chamber systemmanufacturing apparatus, in which a manufacturing process from theformation of a light emitting element to the sealing is automated, isshown in FIG. 12.

[0188] In FIG. 12, a manufacturing apparatus includes: gates 100 a to100 k and 100 m and 100 w, a charging chamber 101, a pick-up chamber119, carrier chambers 102, 104 a, 108, 114 and 118, delivery chambers105, 107 and 111, film formation chambers 106R, 106B, 106G, 106H, 106E,106X, 109, 110, 112 and 113, a pre-processing chamber 103, a sealingsubstrate loading chamber 117, a dispenser chamber 115, a sealingchamber 116, cassette chambers 120 a and 120 b, a tray attachment stage121, and a plasmaetching chamber 122.

[0189] First, a plurality of TFTs, an anode (first electrode) made of atransparent conductive film (ITO (an alloy of indium oxide and tinoxide), an alloy of indium oxide and zinc oxide (In₂O₃—ZnO), zinc oxide(ZnO) and the like) deposited thereon, and an insulator for coveringends of the anode are provided in advance on a substrate. Then, apoly(ethylene dioxythiophene)/poly(styrene sulfonic acid) solution(PEDOT/PSS) acting as a hole injection layer is formed on the entiresurface of the substrate. Then, a heating process in a vacuum isconducted so as to vaporize water. If it is necessary to clean or polishthe surface of the anode, this cleaning or polishing process may beperformed prior to the formation of the film containing PEDOT.

[0190] Hereinafter, a method for carrying the substrate, on which theanode, the insulator for covering the ends of the anode, and the holeinjection layer (film containing PEDOT) are provided in advance, intothe manufacturing apparatus shown in FIG. 12 so as to form a laminatestructure shown in FIG. 9B will be described below.

[0191] First, the substrate is set in any one of the cassette chamber120 a and 120 b. In the case where the substrate is large in size (forexample, 300 mm×360 mm), the substrate is set in the cassette chamber120 b. On the other hand, in the case where the substrate is a normalsubstrate (for example, 127 mm×127 mm), the substrate is carried to thetray attachment stage 121 where a plurality of substrates are placed ona tray (for example, 300 mm×360 mm in size).

[0192] Next, the substrate is carried from the cassette chamber 120 b tothe carrier chamber 118 equipped with a substrate carrier mechanism.Next, the substrate is carried to the film formation chamber 112 wherean layer containing an organic compound made of a polymer acting as alight emitting layer is formed on the entire surface of the holeinjection layer (film containing PEDOT) provided on the entire surfaceof the substrate. The film formation chamber 112 is for forming thelayer containing an organic compound made of a polymer. In thisembodiment, an example where a polyvinyl carbazole (PVK) solution dopedwith a dye acting as a light emitting layer(1,1,4,4-tetraphenyl-1,3-butadiene (TPB),4-dicyanomethylene-2-methyl-6(p-dimethylamino-styryl)-4H-pyran (DCM1),Nile Red, coumarin 6 or the like) is formed on the entire surface, willbe shown. In the case where the layer containing an organic compound isto be formed by spin coating in the film formation chamber 112, asurface of the substrate, on which a film is to be formed, is set so asto be upwardly oriented under an atmospheric pressure. Moreover, afterthe formation of a film using water or an organic solution as a solvent,it is preferred to vaporize water by performing a heating processing ina vacuum. For this purpose, an annealing chamber connected to the filmformation chamber 112, in which the heating under vacuum can beconducted, can be provided.

[0193] Next, the substrate is carried from the carrier chamber 118equipped with the substrate carrier mechanism to the charging chamber101.

[0194] The charging chamber 101 is connected to a vacuum pumpingprocessing chamber. After the vacuum pumping, it is preferred tointroduce an inert gas so that the charging chamber 101 is at anatmospheric pressure. Next, the substrate is carried to the carrierchamber 102 connected to the charging chamber 101. The vacuum pumping isperformed so that water or oxygen is not present as much as possible inthe carrier chamber to maintain the vacuum.

[0195] The carrier chamber 102 is connected to the vacuum pumpingprocessing chamber for evacuating the carrier chamber. As the vacuumpumping processing chamber, a magnetic levitated type turbo molecularpump, a cryopump, or a dry pump is provided. With this vacuum pumpingprocessing chamber, it is possible to set an ultimate degree of vacuumof the carrier chamber at 10⁻⁵ to 10⁻⁶ Pa. Furthermore, it is possibleto control the back diffusion of an impurity from the pump side or anexhaust system. In order to prevent an impurity from being introducedinto the interior of the apparatus, an inert gas such as nitrogen or arare gas is used as a gas to be introduced. As the gas to be introducedinto the apparatus, a gas with a high purity provided by a gaspurification machine before being introduced into the apparatus is used.Therefore, it is necessary to provide a gas purification machine so thatthe gas is introduced into the film formation apparatus after the purityof the gas is increased. As a result, since oxygen, water or otherimpurities contained in the gas can be removed in advance, theseimpurities can be prevented from being introduced into the apparatus.

[0196] After the film is formed by using water or an organic solution asa solvent, it is preferable that the substrate is carried to thepre-processing chamber 103 where a heating processing is performed in ahigh vacuum so as to further vaporize the water.

[0197] In this embodiment, an example where the layer containing anorganic compounds, each being made of a polymeric material, arelaminated is described. In the case where a laminate structure composedof a layer made of a polymeric material and a layer made of a monomericmaterial is to be formed as shown in FIG. 9C or 11A to 11D, films areappropriately formed in the film formation chamber 106R, 106G and 106Bby vapor deposition, so that the layer containing an organic compoundsemitting white light, or red, green or blue light as a whole of thelight emitting element are appropriately formed. The delivery chamber105 is equipped with a substrate reversing mechanism for appropriatelyreversing the substrate.

[0198] Moreover, the electron transport layer or the electron injectionlayer may be appropriately formed in the film formation chamber 106E,whereas the hole injection layer or the hole transport layer may beappropriately formed in the film formation chamber 106H, if needed. Inthe case where the vapor deposition is employed, the vapor deposition isperformed in the film formation chamber which is evacuated to a degreeof vacuum of 5×10⁻³ Torr (0.665 Pa) or lower, preferably, 10⁻⁴ to 10⁻⁶Pa. In vapor deposition, the organic compound is vaporized in advance byresistance heating. A shutter (not shown) is opened upon vapordeposition, so that the organic compound is scattered in a direction ofthe substrate. The vaporized organic compound is upwardly scattered topass through an opening (not shown) provided through a metal mask (notshown) so as to be vapor-deposited on the substrate. In vapordeposition, a temperature (T₁) of the substrate is set at 50 to 200° C.,preferably, 65 to 150° C. by means of heating the substrate. Moreover,in the case where the vapor deposition is employed, it is preferred toset a crucible, in which a vapor-deposition material is received inadvance by a material manufacturer, in the film formation chamber. Uponsetting the crucible, it is preferred to set the crucible withoutcontacting the atmosphere. Moreover, in delivery from a materialmanufacturer, it is preferred to introduce the crucible into the filmformation chamber while being sealed within a second container.Desirably, a chamber having vacuum pumping means is provided so as to bein connection with the film formation chamber 106R. After the crucibleis picked up from the second container in a vacuum or an inert gasatmosphere within this chamber, the crucible is installed in the filmformation chamber. As a result, the crucible and an EL material receivedtherein can be prevented from being contaminated.

[0199] Next, the substrate is carried from the carrier chamber 102 tothe delivery chamber 105, then to the carrier chamber 104 a, further tothe delivery chamber 107 so as not to contact the atmosphere.Thereafter, the substrate is carried from the delivery chamber 107 tothe carrier chamber 108 so as not to contact the atmosphere.

[0200] Next, the substrate is carried, by the carrier mechanism providedin the carrier chamber 108, to the film formation chamber 110 where acathode (a second electrode) formed of a metal film (a film made of analloy such as MgAg, MgIn, AlLi, CaF₂ or CaN, or a film formed byco-depositing an element belonging to Group I or Group II of theperiodic table and aluminum) is formed by vapor deposition employingresistance heating. Upon the vapor deposition, a vapor deposition maskis used to selectively form the cathode.

[0201] Next, the substrate is carried to the plasma processing chamber122 by the carrier mechanism set within the carrier chamber 108 so as toremove layer containing an organic compound made of a polymeric materialin a self-aligned manner using the second electrode as a mask. Theplasma processing chamber 122 has plasma generator means for excitingone or plurality of gases selected from the group consisting of Ar, H, Fand O to generate a plasma for performing the dry etching. If theetching is performed by using the oxygen plasma processing, it is alsopossible to perform the oxygen plasma processing in the pre-processingchamber 103.

[0202] Next, the substrate is carried to the film formation chamber 110again where a third electrode (corresponding to the upper layer of thecathode) made of a metal film (a film made of an alloy such as MgAg,Mgln, AlLi or CaN, or a film formed by co-depositing an elementbelonging to Group I or Group II of the periodic table and aluminum) isformed by vapor deposition using resistance heating. In this case, thethird electrode is formed by a mask different from a vapor depositionmask made of a metal film which is used for the previous vapordeposition, for electrical connection of the second electrode and theconnection wiring. Although the example where the second electrode andthe third electrode are formed in the same film formation chamber 110 isdescribed herein, the efficiency is lowered because it is necessary toreplace a mask by another one. Therefore, in order to improve the task,it is preferred to separately provide film formation chambers for therespective electrodes. Although the example where the third electrode isselectively formed by using a vapor-deposition mask is described in thisembodiment, the third electrode may also be patterned by etching with aphotoresist after formation of the metal film by sputtering.

[0203] As a result of the above steps, a light emitting element having alaminate structure shown in FIG. 9B is formed.

[0204] Next, the light emitting element is carried from the carrierchamber 108 to the film formation chamber 113 without contacting theatmosphere, where a protective film made of a silicon nitride film or asilicon oxynitride film is formed. Herein, a sputtering device includinga target made of silicon, silicon oxide or silicon nitride is providedin the film formation chamber 113. For example, an ambient in the filmformation chamber can be made to be a nitrogen ambient or an ambientcontaining nitrogen and argon by using a target made of silicon so as toform a silicon nitride film.

[0205] Next, the substrate on which the light emitting element is formedis carried from the carrier chamber 108 to the delivery chamber 111,then to the carrier chamber 114, so as not to contact the atmosphere.

[0206] Next, the substrate, on which the light emitting element isformed, is carried from the carrier chamber 114 to the sealing chamber116. Note that, it is preferred to prepare a sealing substrate, on whicha sealing material is provided, in the sealing chamber 116.

[0207] The sealing substrate is set in the sealing substrate loadingchamber 117 from the exterior. It is preferred to perform annealing in avacuum in advance, for example, to perform annealing within the sealingsubstrate loading chamber 117, so as to remove an impurity such aswater. Then, in the case where a sealing material is to be formed on thesealing substrate, the carrier chamber 114 is set at an atmosphericpressure. Thereafter, the sealing substrate is carried from the sealingsubstrate loading chamber 117 to the dispenser chamber 115 where thesealing material for attachment with the substrate including the lightemitting element provided thereon is formed. Then, the sealingsubstrate, on which the sealing material is formed, is carried to thesealing chamber 116.

[0208] Next, in order to degas the substrate on which the light emittingelement is provided, the annealing is performed in a vacuum or an inertambient. Thereafter, the sealing substrate, on which the sealingmaterial is provided, and the substrate, on which the light emittingelement is formed, are bonded to each other. The sealed space is filledwith hydrogen or an inert gas. Although the example where the sealingmaterial is formed on the sealing substrate is described herein, theregion where the sealing material is provided is not particularlylimited thereto. The sealing material may be formed on the substrate onwhich the light emitting element is formed.

[0209] Next, a pair of the bonded substrates are irradiated with UVlight by a ultraviolet-ray irradiation mechanism provided in the sealingchamber 116 so as to cure the sealing material. Although a ultravioletcurable resin is used as the sealing material herein, the type of thesealing material is not particularly limited as long as the sealingmaterial is an adhesive.

[0210] Next, a pair of the bonded substrates are carried from thesealing chamber 116 to the carrier chamber 114, then to the pick-upchamber 119 where the bonded substrates are picked up.

[0211] As described above, the light emitting element is not exposed tothe exterior owing to the manufacturing apparatus shown in FIG. 12 untilthe light emitting element is completely sealed within a sealed space.Therefore, it is possible to manufacture a highly reliable lightemitting device. A nitrogen ambient in vacuum and that at an atmosphericpressure are alternated in the carrier chamber 114, whereas it isdesirable to always keep the vacuum in the carrier chambers 102, 104 aand 108.

[0212] Alternatively, the film formation apparatus may also beconstituted as an inline system apparatus.

[0213] A procedure for carrying a substrate into the manufacturingapparatus shown in FIG. 12 so as to form a light emitting element havingan opposite light emission direction to that of the above-describedlaminate structure by using a metal film (a metal having a large workfunction (Pt, Cr, W, Ni, Zn, Sn, In or the like) as an anode will bedescribed below.

[0214] First, a poly(ethylene dioxythiophene)/poly(styrene sulfonicacid) solution (PEDOT/PSS) acting as a hole injection layer is formed onthe entire surface of the substrate on which a plurality of TFTs, theanode, and the insulator for covering the ends of the anode are providedin advance. Then, a heating process is performed in a vacuum so as tovaporize the water.

[0215] Next, the substrate, on which the TFTs and the anode areprovided, is set in either the cassette chamber 120 a or 120 b.

[0216] Then, the substrate is carried from the cassette chamber 120 a or120 b to the carrier chamber 118 equipped with the substrate carriermechanism.

[0217] Next, the substrate is carried to the film formation chamber 112where the layer containing an organic compound made of a polymer servingas a light emitting layer is formed on the entire surface of the holeinjection layer (a film containing PEDOT) which is formed on the entiresurface of the substrate. The film formation chamber 112 is for formingthe layer containing an organic compound made of a polymer. In thisembodiment, an example where a polyvinyl carbazole (PVK) solution dopedwith a dye acting as a light emitting layer(1,1,4,4-tetraphenyl-1,3-butadiene (TPB),4-dicyanomethylene-2-methyl-6(p-dimethylamino-styryl)-4H-pyran (DCM1),Nile Red, coumarin 6 or the like is formed on the entire surface of thehole injection layer is described. In the case where the layercontaining an organic compound is to be formed by spin coating in thefilm formation chamber 112, the substrate is set under the atmosphericpressure so that its face on which the film is to be formed is upwardlyoriented.

[0218] Next, the substrate is carried from the carrier chamber 118equipped with the substrate carrier mechanism to the charging chamber101. Then, the substrate is carried to the carrier chamber 102 connectedto the charging chamber 101. After the film is formed by using water oran organic solution as a solvent, it is preferred that the substrate iscarried to the pre-processing chamber 103 where a heating process isperformed in a vacuum so as to vaporize the water.

[0219] Next, the substrate is carried from the carrier chamber 102 tothe delivery chamber 105, then to the carrier chamber 104 a, further tothe delivery chamber 107 so as not to contact the atmosphere.Thereafter, the substrate is carried from the delivery chamber 107 tothe carrier chamber 108 so as not to contact the atmosphere.

[0220] Next, the substrate is carried, by the carrier mechanism providedin the carrier chamber 108, to the film formation chamber 110 where acathode (lower layer) formed of an extremely thin metal film (a filmmade of an alloy such as MgAg, MgIn, AlLi or CaN, or a film formed byco-depositing an element belonging to Group I or Group II of theperiodic table and aluminum) is formed by vapor deposition employingresistance heating. After formation of the cathode (lower layer) made ofa thin metal layer, the substrate is carried to the film formationchamber 109 where a cathode (upper layer) made of a transparentconductive film (ITO (an alloy of indium oxide and tin oxide), an alloyof indium oxide and zinc oxide (In₂O₃—ZnO), zinc oxide (ZnO) and thelike) is formed by sputtering. Then, the cathode (second electrode) madeof a laminate of a thin metal layer and a transparent conductive film isappropriately formed by using a metal mask and the like.

[0221] Next, the substrate is carried to the plasma processing chamber122 by the carrier mechanism set within the carrier chamber 108 so as toremove the laminate layer of the organic compound films made of apolymeric material in a self-aligned manner using the second electrodeas a mask. The plasma processing chamber 122 has plasma generator meansfor exciting one or plurality of gases selected from the groupconsisting of Ar, H, F and O to generate a plasma for performing the dryetching. If the etching is performed by using the oxygen plasmaprocessing, it is also possible to perform the oxygen plasma processingin the pre-processing chamber 103.

[0222] Next, the substrate is carried to the film formation chamber 109again where a third electrode (corresponding to the upper layer of thecathode) made of a transparent conductive film is formed by sputtering.In this case, the third electrode is formed by changing the metal maskwith the pattern different from one used for the previously formedsecond electrode, for electrical connection between the second electrodeand the connection wiring. Although an example where the third electrodeis selectively formed by using a mask is described in Embodiment 2, thethird electrode may also be patterned by etching with a photoresist.

[0223] By the above-described steps, the light emitting element, fromwhich light transmitted through the second electrode is obtained, isformed.

[0224] Moreover, since the subsequent steps are the same as those in theabove-described manufacturing procedure for the light emitting devicehaving a laminate structure shown in FIG. 9B, the description thereof isherein omitted.

[0225] Although the example where the method described in Embodiment 4for electrically connecting the second electrode and the connectionwiring to each other by forming the third electrode has been describedin this embodiment, a method for electrically connecting the secondelectrode and the connection wiring to each other is not particularlylimited thereto. The second electrode and the connection wiring may beconnected to each other by any one of the methods described inEmbodiment Modes 1 to 3.

[0226] Moreover, this embodiment can be freely combined with Embodiment1.

[0227] [Embodiment 3]

[0228] By implementing the present invention, all of the electronicappliances into which a module including organic light emitting elements(an active matrix EL module) is built is completed.

[0229] Following can be given as such electronic appliances: videocameras; digital cameras; head mounted displays (goggle type displays);car navigation systems; projectors; car stereos; personal computers;portable information terminals (mobile computers, mobile phones orelectronic books etc.) etc. Examples of these are shown in FIGS. 13A to13F and 14A to 14C.

[0230]FIG. 13A is a personal computer which comprises: a main body 2001;an image input section 2002; a display section 2003; and a keyboard 2004etc.

[0231]FIG. 13B is a video camera which comprises: a main body 2101; adisplay section 2102; a voice input section 2103; operation switches2104; a battery 2105 and an image receiving section 2106 etc.

[0232]FIG. 13C is a mobile computer which comprises: a main body 2201; acamera section 2202; an image receiving section 2203; operation switches2204 and a display section 2205 etc.

[0233]FIG. 13D is a goggle type display which comprises: a main body2301; a display section 2302; and an arm section 2303 etc.

[0234]FIG. 13E is a player using a recording medium in which a programis recorded (hereinafter referred to as a recording medium) whichcomprises: a main body 2401; a display section 2402; a speaker section2403; a recording medium 2404; and operation switches 2405 etc. Thisapparatus uses DVD (digital versatile disc), CD, etc. for the recordingmedium, and can perform music appreciation, film appreciation, games anduse for Internet.

[0235]FIG. 13F is a digital camera which comprises: a main body 2501; adisplay section 2502; a view finder 2503; operation switches 2504; andan image receiving section (not shown in the figure) etc.

[0236]FIG. 14A is a mobile phone which comprises: a main body 2901; avoice output section 2902; a voice input section 2903; a display portion2904; operation switches 2905; an antenna 2906; and an image inputsection (CCD, image sensor, etc.) 2907 etc.

[0237]FIG. 14B is a portable book (electronic book) which comprises: amain body 3001; display portions 3002 and 3003; a recording medium 3004;operation switches 3005 and an antenna 3006 etc.

[0238]FIG. 14C is a display which comprises: a main body 3101; asupporting section 3102; and a display portion 3103 etc.

[0239] In addition, the display shown in FIG. 14C has small andmedium-sized or large-sized screen, for example a size of 5 to 20inches. Further, it is preferable to mass-produce by executing amultiple pattern using a substrate sized 1 m×1 m to form such sizeddisplay portion.

[0240] As described above, the applicable range of the present inventionis extremely large, and the invention can be applied to electronicappliances of various areas. Note that the electronic appliances of thisembodiment can be achieved by utilizing any combination of constitutionsin Embodiment Modes 1 to 4, and Embodiments 1 and 2.

[0241] [Embodiment 4]

[0242] Although an example of the insulator having the first and secondcurvature radii has been described in Embodiment Mode 4, an examplewhere only the upper end of the insulator has a curvature radius isshown in FIGS. 19A to 19C in this embodiment.

[0243] Although a structure other than the insulator is the same as thatof Embodiment Mode 4 in this embodiment, the structure is notparticularly limited thereto. Instead of the insulators shown inEmbodiment Modes 1 to 3, the insulator shown in this embodiment can beapplied.

[0244] In FIGS. 19A to 19C, a light emitting device includes an layer 80containing an organic compound, a second electrode 81, a connectionwiring 87, an insulator 88, a first electrode 89, a third electrode 91,and a light emitting device 93. As the insulator 88, it is preferred touse a negative type organic material which is rendered insoluble to anetchant by light or a positive type organic material which is renderedsoluble to an etchant by light.

[0245] In this embodiment, the insulator 88 is formed by a positive-typephotoresist. The insulator 88 shown in FIG. 19A is formed by adjustingthe exposure conditions or etchant conditions. The insulator 88 has acurvature radius of 0.2 to 3 μm only on its upper end. The insulator 88can provide good coverage for the layer 80 containing an organiccompound or the second electrode 81 made of a metal film. At the sametime, the defect called shrink, i.e., reduction in light emitting area,can be reduced. The same shape as that of the insulator 88 shown in FIG.19A is formed on a glass substrate by using a positive type acrylicresin. A photograph of its cross section obtained through observation ofthe acrylic resin is shown in FIG. 20. A taper angle on the side face ofthe insulator 88 may be 45°±10°.

[0246] Moreover, FIG. 19B shows an example where a laminate layercomposed of an upper layer 98 b made of a photoresist serving as aphotosensitive organic material and a lower layer 98 a made of acrylicserving as a non-photosensitive organic material is used as theinsulator. The upper layer 98 b of the insulator has a curvature radiusof 0.2 to 3 μm only on its upper end. Instead of using thenon-photosensitive material, an inorganic material (silicon oxide,silicon nitride, silicon oxynitride or the like) can be used as thelower layer 98 a of the insulator.

[0247]FIG. 19C shows an example where a silicon nitride film 94 isformed by RF sputtering on the insulator 88. Instead of using thesilicon nitride film 94, a silicon oxynitride film or a film representedby AlN_(X)O_(Y) can be used. The film represented by AlN_(X)O_(Y) may beformed by sputtering using a target made of AlN or Al while introducingoxygen, nitrogen or a rare gas from the gas introduction system. It issufficient for the film represented by AlN_(X)O_(Y) to contain nitrogenat several atm % or more, preferably, 2.5 atm % to 47.5 atm % and oxygenat 47.5 atm % or less, preferably, 0.01 to less than 20 atm %. Theprotective film such as a silicon nitride film is formed on theinsulator 88, so that a defect called shrink, i.e., reduction in lightemitting area, can be reduced.

[0248] Moreover, this embodiment can be combined with any one ofEmbodiment Modes 1 to 4 and Embodiments 1 to 3.

[0249] According to the present invention, an layer containing anorganic compound can be selectively formed. As a result, a structure, inwhich the layer containing an organic compound is not formed at ajunction of a wiring connected to the external power source, can beeasily formed.

[0250] Moreover, according to the present invention, the color filter isprovided to eliminate the necessity of a circular polarizing plate so asto reduce the cost. At the same time, since it is not necessary toseparately color the light emitting elements owing to the color filter,the improvement in throughput as well as in definition can be realized.

What is claimed is:
 1. A light emitting device comprising: a pixelportion including a plurality of light emitting elements, a drivingcircuit and a terminal portion, between a first substrate having aninsulating surface and a second substrate having translucency, each ofthe light emitting elements including: a first electrode; a layercontaining an organic compound on the first electrode; and a secondelectrode on the layer containing the organic compound, wherein theterminal portion is placed on the first substrate so as to be positionedoutside the second substrate; and wherein the first substrate and thesecond substrate are bonded to each other through an adhesive in whichconductive fine particles having different diameters are mixed, whereasthe second electrode and a wiring from the terminal portion areelectrically connected to each other.
 2. A light emitting deviceaccording to claim 1, wherein the second electrode is each one of ananode and a cathode of one of the light emitting elements.
 3. A lightemitting device according to claim 1, wherein the second electrode hasthe same pattern form as that of the layer containing the organiccompound.
 4. A light emitting device according to claim 1, wherein theorganic compound is made of a polymeric material.
 5. A light emittingdevice according to claim 1, wherein the layer containing the organiccompound comprises a layer made of a polymeric material and a layer madeof a monomeric material.
 6. A light emitting device according to claim1, wherein an end of the first electrode is covered with an insulator,and an upper end of the insulator includes a curved surface having afirst curvature radius whereas a lower end of the insulator includes acurved surface having a second curvature radius, the first curvatureradius and the second curvature radius being 0.2 to 3 μm.
 7. A lightemitting device according to claim 1, wherein the first electrode ismade of a material having translucency, and is one of an anode and acathode of one of the light emitting elements.
 8. A light emittingdevice according to claim 1, wherein the light emitting elements emitwhite light, and are combined with color filters.
 9. A light emittingdevice according to claim 1, wherein the light emitting elements emitmonochromatic light, and are combined with color converting layers orcolored layers.
 10. A light emitting element according to claim 1,wherein the light emitting device is any one of a video camera, adigital camera, a goggle-type display, a car navigation system, apersonal computer and a portable information terminal.
 11. A lightemitting device comprising: a pixel portion including a plurality oflight emitting elements, a driving circuit and a terminal portion,between a first substrate having an insulating surface and a secondsubstrate having translucency, each of the light emitting elementsincluding: a first electrode; a layer containing an organic compound onthe first electrode; and a second electrode on the layer containing theorganic compound, wherein the terminal portion is placed on the firstsubstrate so as to be positioned outside the second substrate; andwherein the first substrate and the second substrate are bonded to eachother through an adhesive in which a fine particle made of an inorganicmaterial and a conductive fine particle having a larger diameter thanthat of the fine particle are mixed, whereas the second electrode and awiring from the terminal portion are electrically connected to eachother.
 12. A light emitting device according to claim 11, wherein thesecond electrode is each one of an anode and a cathode of one of thelight emitting elements.
 13. A light emitting device according to claim11, wherein the second electrode has the same pattern form as that ofthe layer containing the organic compound.
 14. A light emitting deviceaccording to claim 11, wherein the organic compound is made of apolymeric material.
 15. A light emitting device according to claim 11,wherein the layer containing the organic compound comprises a layer madeof a polymeric material and a layer made of a monomeric material.
 16. Alight emitting device according to claim 11, wherein an end of the firstelectrode is covered with an insulator, and an upper end of theinsulator includes a curved surface having a first curvature radiuswhereas a lower end of the insulator includes a curved surface having asecond curvature radius, the first curvature radius and the secondcurvature radius being 0.2 to 3 μm.
 17. A light emitting deviceaccording to claim 11, wherein the first electrode is made of a materialhaving translucency, and is one of an anode and a cathode of one of thelight emitting elements.
 18. A light emitting device according to claim11, wherein the light emitting elements emit white light, and arecombined with color filters.
 19. A light emitting device according toclaim 11, wherein the light emitting elements emit monochromatic light,and are combined with color converting layers or colored layers.
 20. Alight emitting element according to claim 11, wherein the light emittingdevice is any one of a video camera, a digital camera, a goggle-typedisplay, a car navigation system, a personal computer and a portableinformation terminal.
 21. A light emitting device comprising: a pixelportion including a plurality of light emitting elements, each of thelight emitting elements including: a first electrode; a layer containingan organic compound on the first electrode; and a second electrode onthe layer containing the organic compound; and a terminal portion,wherein an end face of the layer containing the organic compound isflush with that of the second electrode; and wherein there is a portionwhere the second electrode and a wiring extending from the terminalportion are electrically connected through an adhesive containing aconductive fine particle, between the terminal portion and the pixelportion.
 22. A light emitting device according to claim 21, wherein thesecond electrode is each one of an anode and a cathode of one of thelight emitting elements.
 23. A light emitting device according to claim21, wherein the organic compound is made of a polymeric material.
 24. Alight emitting device according to claim 21, wherein the layercontaining the organic compound comprises a layer made of a polymericmaterial and a layer made of a monomeric material.
 25. A light emittingdevice according to claim 21, wherein an end of the first electrode iscovered with an insulator, and an upper end of the insulator includes acurved surface having a first curvature radius whereas a lower end ofthe insulator includes a curved surface having a second curvatureradius, the first curvature radius and the second curvature radius being0.2 to 3 μm.
 26. A light emitting device according to claim 21, whereinthe first electrode is made of a material having translucency, and isone of an anode and a cathode of one of the light emitting elements. 27.A light emitting device according to claim 21, wherein the lightemitting elements emit white light, and are combined with color filters.28. A light emitting device according to claim 21, wherein the lightemitting elements emit monochromatic light, and are combined with colorconverting layers or colored layers.
 29. A light emitting elementaccording to claim 21, wherein the light emitting device is any one of avideo camera, a digital camera, a goggle-type display, a car navigationsystem, a personal computer and a portable information terminal.
 30. Alight emitting device comprising: a pixel portion including a pluralityof light emitting elements, each of the light emitting elementsincluding: a first electrode; a layer containing an organic compound onthe first electrode; and a second electrode on the layer containing theorganic compound; and a terminal portion, wherein an end face of thelayer containing the organic compound is flush with that of the secondelectrode; and wherein there is a portion where the second electrode anda wiring extending from the terminal portion are connected through athird electrode covering the second electrode, between the terminalportion and the pixel portion.
 31. A light emitting device according toclaim 30, wherein the third electrode is made of a metal.
 32. A lightemitting device according to claim 30, wherein the second electrode andthe third electrode are each one of an anode and a cathode of one of thelight emitting elements.
 33. A light emitting device according to claim30, wherein the organic compound is made of a polymeric material.
 34. Alight emitting device according to claim 30, wherein the layercontaining the organic compound comprises a layer made of a polymericmaterial and a layer made of a monomeric material.
 35. A light emittingdevice according to claim 30, wherein an end of the first electrode iscovered with an insulator, and an upper end of the insulator includes acurved surface having a first curvature radius whereas a lower end ofthe insulator includes a curved surface having a second curvatureradius, the first curvature radius and the second curvature radius being0.2 to 3 μm.
 36. A light emitting device according to claim 30, whereinthe first electrode is made of a material having translucency, and isone of an anode and a cathode of one of the light emitting elements. 37.A light emitting device according to claim 30, wherein the lightemitting elements emit white light, and are combined with color filters.38. A light emitting device according to claim 30, wherein the lightemitting elements emit monochromatic light, and are combined with colorconverting layers or colored layers.
 39. A light emitting elementaccording to claim 30, wherein the light emitting device is any one of avideo camera, a digital camera, a goggle-type display, a car navigationsystem, a personal computer and a portable information terminal.
 40. Amethod of manufacturing a light emitting device including a lightemitting element having: an anode; a layer containing an organiccompound on the anode; and a cathode on the layer containing the organiccompound, comprising: forming a first electrode having translucency;forming the layer containing the organic compound by application on thefirst electrode; selectively forming a second electrode made of a metalon the layer containing the organic compound by vapor deposition ofheating a vapor deposition material; etching the layer containing theorganic compound in a self-aligned manner by plasma etching using thesecond electrode as a mask; and selectively forming a third electrodemade of a metal so as to cover the second electrode.
 41. A method ofmanufacturing a light emitting device according to claim 40, wherein thesecond electrode and the third electrode are each one of the anode andthe cathode of the light emitting element.
 42. A method of manufacturinga light emitting device according to claim 40, wherein the thirdelectrode is formed by using any one of vapor deposition and sputtering.43. A method of manufacturing a light emitting device according to claim40, wherein the plasma is generated by exciting one or a plurality ofgases selected from the group consisting of: Ar, H, F and O.
 44. Amethod of manufacturing a light emitting device according to claim 40,wherein the first electrode is one of the anode and the cathode of thelight emitting element electrically connected to a TFT.
 45. A method ofmanufacturing a light emitting device including a light emitting elementhaving: an anode; a layer containing an organic compound on the anode;and a cathode on the layer containing the organic compound, comprising:forming a first electrode having translucency; forming the layercontaining the organic compound by application on the first electrode;selectively forming a second electrode made of a metal on the layercontaining the organic compound by vapor deposition of heating a vapordeposition material; etching the layer containing the organic compoundin a self-aligned manner by plasma etching using the second electrode asa mask; and connecting the second electrode and a wiring extending froma terminal portion to each other through an adhesive containing aconductive particle.
 46. A method of manufacturing a light emittingdevice according to claim 45, wherein the second electrode is each oneof the anode and the cathode of the light emitting element.
 47. A methodof manufacturing a light emitting device according to claim 45, whereinthe plasma is generated by exciting one or a plurality of gases selectedfrom the group consisting of: Ar, H, F and O.
 48. A method ofmanufacturing a light emitting device according to claim 45, wherein thefirst electrode is one of the anode and the cathode of the lightemitting element electrically connected to a TFT.
 49. A method ofmanufacturing a light emitting device including a light emitting elementhaving: an anode; a layer containing an organic compound on the anode;and a cathode on the layer containing the organic compound, comprising:forming a thin film transistor on a first substrate; forming a firstelectrode to be connected to the thin film transistor; forming the layercontaining the organic compound, made of a polymeric material, byapplication on the first electrode; selectively forming a secondelectrode made of a metal on the layer containing the organic compoundby vapor deposition of heating a vapor deposition material; etching thelayer containing the organic compound in a self-aligned manner by plasmaetching using the second electrode as a mask; and connecting the secondelectrode and a wiring extending from a terminal portion to each otherthrough an adhesive containing a conductive particle, while bonding thefirst substrate and a second substrate to each other.
 50. A method ofmanufacturing a light emitting device according to claim 49, wherein thesecond electrode is each one of the anode and the cathode of the lightemitting element.
 51. A method of manufacturing a light emitting deviceaccording to claim 49, wherein the plasma is generated by exciting oneor a plurality of gases selected from the group consisting of: Ar, H, Fand O.
 52. A method of manufacturing a light emitting device accordingto claim 49, wherein the first electrode is one of the anode and thecathode of the light emitting element electrically connected to a TFT.